NASA will say goodbye to the International Space Station in 2030 − and welcome in the age of commercial space stations

A space station hangs in black.

This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights.

For 24 hours a day, seven days a week since November 2000, NASA and its international partners have sustained a continuous human presence in low-Earth orbit, including at least one American – a streak that will soon reach 25 years.